The CD contains twenty WAD files created by various authors under contract. The file teeth.wad contains a secret level, so there are a total of 21 levels.
As a bonus, a poster and 1830 amateur PWAD files downloaded from the internet (collectively called Maximum Doom) are also included. Also of note is that some of the contracted designers for the Master Levels had levels they had previously released on the internet that were included in Maximum Doom.
- Geryon: 6th Canto of Inferno (GERYON.WAD)
- Minos' Judgement: 4th Canto of Inferno (MINOS.WAD)
- Nessus: 5th Canto of Inferno (NESSUS.WAD)
- Vesperas: 7th Canto of Inferno (VESPERAS.WAD)
- Virgil's Lead: 3rd Canto of Inferno (VIRGIL.WAD)
- The Catwalk (CATWALK.WAD)
- The Combine (COMBINE.WAD)
- The Fistula (FISTULA.WAD)
- The Garrison (GARRISON.WAD)
- Subspace (SUBSPACE.WAD)
- Subterra (SUBTERRA.WAD)
- Black Tower (BLACKTWR.WAD)
- Bloodsea Keep (BLOODSEA.WAD)
- Mephisto's Maosoleum (MEPHISTO.WAD)
- Paradox (PARADOX.WAD)
Master Levels Menu Interface Edit
The Master_Levels_Menu_Interface at the ZDoom wiki is a 2010 ZDoom WAD created by Zippy which is designed to replicate the menu functionality of Doom-It in-game and allow all 21 levels to be played without restarting the engine each time. Once the WADs are added, the Menu Interface can be loaded in ZDoom, and used to play each WAD at any skill level in whichever order the user wants; they will be returned to the menu each time they complete a level.